"Crime is a disease, and Lt. Marion Cobretti, affectionately known as Cobra (Sylvester Stallone), is the cure." This tough, sunglasses-clad cop approaches law enforcement with a no-nonsense attitude, often disregarding the rules in his singular pursuit of justice. With a reliable pearl-handled Colt .45 as his partner in crime-fighting, Cobra's methods are relentlessly effective, albeit controversial.
The city faces a terrifying new threat as a killer cult emerges, ruthlessly hunting innocent victims with their jagged knives, reveling in the fear they instill. Their fatal mistake occurs when they murder a woman at a bus stop, witnessed by a terrified young model named Ingrid (Brigitte Nielsen). Though she doesn't fully understand the gravity of the situation, the chilling gaze of one of the cult's members, a muscle-bound, grotesquely disfigured man, leaves her shaken.
Ingrim's life becomes endangered as the cult targets her, leading to the brutal murder of her photographer and a security guard. Fortunately, Cobra, alongside his junk food-loving partner, Sergeant Gonzales, springs into action. They question Ingrid about her experience. She shares that she noticed odd behavior at the bus stop and was frightened by a man, but details are sparse, preventing Cobra from making immediate progress.
Cobra's uncompromising style soon puts him at odds with the overzealous Detective Monte, who is determined to keep Cobra's aggression in check. Despite Monte's protests, both the Chief and Captain Sears authorize Cobra to leverage his street smarts to confront the killers. Cobra delves into the seedy underbelly of the city, mingling with prostitutes, pimps, and other renegades, but the hunt yields little information.
He connects a supermarket murder involving a madman proclaiming himself a member of "the new order" to the cult's activities. However, Detective Monte's condescending attitude, coupled with Captain Sears' lack of spine, create substantial barriers for Cobra, especially given that Ingrid had a close brush with death. Eventually, the Captain allows Cobra to take Ingrid to the countryside, accompanied by Gonzales and a female officer named Nancy Stalk. Unbeknownst to them, Nancy is secretly aligned with the cult and leads the Night Slasher and his followers directly to them.
In a secluded motel, tensions flare as Cobra and Ingrid discover their mutual attraction. However, their romantic interlude is shattered when the cult tracks them down, burning down the motel and putting Gonzales's life in jeopardy. In a daring escape, Cobra and Ingrid manage to flee in a pickup truck, narrowly avoiding a fiery wreck.
The pair eventually find themselves in a chemical factory, where the ultimate showdown occurs between Cobra and the Night Slasher. The latter, in a deranged tirade, insists that Cobra's version of justice is weak, assuring him that their cult will endure. But fate takes a grisly turn as Cobra retaliates, leading to the Night Slasher's demise in a molten vat of metal.
After navigating the chaos and carnage, Cobra and Ingrid emerge battered but triumphant. Although the Captain offers congratulations, Monte stubbornly clings to his beliefs about Cobra’s excessive force. That is until Cobra, frustrated, delivers a well-deserved punch that leaves Monte reeling on the ground. As the dust settles, Cobra and Ingrid ride off into the sunset on a motorbike, with the echoes of a romantic tune—“Can you get enough of me, baby? I can't get enough of you”—playing in the background, encapsulating the thrilling culmination of their battle against evil and the blossoming of their relationship.
